Chapter 14 explores the complex and shifting views on justification that emerged during the Reformed evangelical groups in Zurich, Strasbourg and Geneva over the period 1519 to 1560. Early Reformed theologies of justification, such as that of Zwingli, tended to reflect an Erasmian perspective, seeing justification as one of several ways of framing the transformation of the life of faith through divine grace. However, a growing awareness of the views emerging within the Wittenberg evangelical movement led to more emphasis being placed on the notion of justification, which increasingly came to be understood in a forensic manner. Bucer’s theology of justification can be seen as an important landmark in this process of transition, which is generally considered to have been completed through the theological synthesis achieved by John Calvin in Geneva, particularly in the 1559 edition of his Institutes of the Christian Religion.Calvin’s approach placed an emphasis on the importance of ‘union with Christ’ as a framework for understanding justification as a forensic category, linked with the essentially transformist notion of sanctification.